1. Field of the Invention
The present invention relates to a type of ophthalmic apparatus in which the components are separated, a representative thereof being a hand-held apparatus and a receiver, and more particularly, relates to ophthalmic apparatus capable of wireless communication between the components.
2. Description of Related Art
Ophthalmic examining apparatus, for instance, an objective type, refracting power measurement apparatus and a cornea shape measurement apparatus or the like, consists of various parts such as an observing part, measuring part, displaying part and recording part. Such ophthalmic apparatus comprising so many parts can be large and heavy, and not easily moved about.
The recent rapid progress of electronics, however, has enabled miniaturization of various devices and, even in the ophthalmic field, miniaturization of hand-held type apparatus for examining the eye.
As a hand-held type of ophthalmic apparatus, known are apparatus for mainly observing, such as a retinoscope and an ophthalmoscope or the like, and recently, a hand-held type of apparatus having a measuring system which can be miniaturized, an example of which is a contact type tonometer.
A hand-held type ophthalmic apparatus that includes a measurement system for measuring tension of an eye or other uses ought to be compact and light in order to be easily portable and not burdened with additional apparatus, e.g., a printer, and thus increased weight. Accordingly, conceivable is apparatus that is separated into a unit comprising internal measurement with a data displaying system and another unit such as a printing device and the like, which is kept separate because of weight and other factors. For communication of measurement data between units of such separate type apparatus, most easily, the units are connected with each other by cables; RS-232C for serial communication, Centronics for parallel communication for example).
Commonly, ophthalmic apparatus comprising a measurement system is also provided with other systems for displaying, recording measured data and transmitting such data to a host computer. However, conventional hand-held type apparatus, being not provided with recording and data transmitting systems, can not be used in the same manner as general apparatus.
If the measuring and other units are connected with each other by cables, there occurs the problem that these cables may be an obstacle to measurement operation, and the maintenance of a cable can be difficult because a cable is liable to break down.